| 摘要 |
<p>A method for forming a BICMOS device having MOS devices and bipolar devices formed during the same process includes the step of first forming bipolar (22) and MOS (24) regions and then forming gate electrodes (50) in the MOS regions and poly emitters (56) in the bipolar regions. The gate electrodes (50) and poly emitters (56) have a layer of refractory metal (52, 58) formed on the upper surface thereof and covered by a protective cap (54, 60). The extrinsic bases (120, 122) formed on either side of the emitter electrode (56) and the source/drain regions (116, 118) are formed on either side of the gate electrode (50) by forming a layer of silicide (78, 80, 84, 86) and implanting the layer of silicide (78, 80, 84, 86) with p-type impurities which are subsequently driven downward. The protective cap (60) prevents the p-type impurities from being introduced into the poly emitter (56).</p> |
